}         } // end anonymous inner class      ); // end call to addActionListener      // set up startJButton      startJButton = new JButton();      startJButton.setBounds( 7, 171, 64, 24 );      startJButton.setText( "Start" );      controlJPanel.add( startJButton );      startJButton.addActionListener(         new ActionListener() // anonymous inner class         {            // event handler called when startJButton is pressed            public void actionPerformed( ActionEvent event )            {               startJButtonActionPerformed( event );            }         } // end anonymous inner class      ); // end call to addActionListener      // set up clearJButton      clearJButton = new JButton();      clearJButton.setBounds( 79, 171, 64, 24 );      clearJButton.setText( "Clear" );      controlJPanel.add( clearJButton );      clearJButton.addActionListener(         new ActionListener() // anonymous inner class         {            // event handler called when clearJButton is pressed            public void actionPerformed( ActionEvent event )            {               clearJButtonActionPerformed( event );            }         } // end anonymous inner class      ); // end call to addActionListener      // set up timerActionListener      ActionListener timerActionListener =          new ActionListener() // anonymous inner class         {            // event handler called every 1000 milliseconds            public void actionPerformed( ActionEvent event )            {               clockTimerActionPerformed( event );            }         }; // end anonymous inner class      // set up clockTimer      clockTimer = new Timer( 1000, timerActionListener );      // set properties of application's window      setTitle( "Microwave Oven" ); // set title bar string      setSize( 536, 261 );          // set window size      setVisible( true );           // display window   } // end method createUserInterface   // add digit 1 to timeToDisplay   private void oneJButtonActionPerformed( ActionEvent event )   {      displayTime( "1" ); // display time input properly   } // end method oneJButtonActionPerformed   // add digit 2 to timeToDisplay   private void twoJButtonActionPerformed( ActionEvent event )   {      displayTime( "2" ); // display time input properly   } // end method twoJButtonActionPerformed   // add digit 3 to timeToDisplay   private void threeJButtonActionPerformed( ActionEvent event )   {      displayTime( "3" ); // display time input properly   } // end method threeJButtonActionPerformed   // add digit 4 to timeToDisplay   private void fourJButtonActionPerformed( ActionEvent event )   {      displayTime( "4" ); // display time input properly   } // end method fourJButtonActionPerformed   // add digit 5 to timeToDisplay   private void fiveJButtonActionPerformed( ActionEvent event )   {      displayTime( "5" ); // display time input properly   } // end method fiveJButtonActionPerformed   // add digit 6 to timeToDisplay   private void sixJButtonActionPerformed( ActionEvent event )   {      displayTime( "6" ); // display time input properly   } // end method sixJButtonActionPerformed   // add digit 7 to timeToDisplay   private void sevenJButtonActionPerformed( ActionEvent event )   {      displayTime( "7" ); // display time input properly   } // end method sevenJButtonActionPerformed   // add digit 8 to timeToDisplay   private void eightJButtonActionPerformed( ActionEvent event )   {      displayTime( "8" ); // display time input properly   } // end method eightJButtonActionPerformed   // add digit 9 to timeToDisplay   private void nineJButtonActionPerformed( ActionEvent event )   {      displayTime( "9" ); // display time input properly   } // end method nineJButtonActionPerformed      // add digit 0 to timeToDisplay   private void zeroJButtonActionPerformed( ActionEvent event )   {      displayTime( "0" ); // display time input properly   } // end method zeroJButtonActionPerformed      // format the time so that it has exactly four digits   private String formatTime()   {      // declare String currentTime to manipulate output      String currentTime = timeToDisplay;      // add zeros until currentTime is at least 4 characters long      for ( int i = currentTime.length(); i < 4; i++ )      {         currentTime = "0" + currentTime;      }      // if the length of currentTime is greater than four      if ( currentTime.length() > 4 )      {         // shorten currentTime to the first four characters         currentTime = currentTime.substring( 0, 4 );      }      return currentTime;   } // end method formatTime      // start the microwave oven   private void startJButtonActionPerformed( ActionEvent event )   {      // get the time as four digits      String fourDigitTime = formatTime();      // extract minutes and seconds      String minute = fourDigitTime.substring( 0, 2 );      String second = fourDigitTime.substring( 2 );            // initialize CookingTime object to time entered by user      microwaveTime.setMinute( Integer.parseInt( minute ) );      microwaveTime.setSecond( Integer.parseInt( second ) );            // display formatted starting time in displayJTextField      displayJTextField.setText( timeFormat.format(          microwaveTime.getMinute() ) + ":" + timeFormat.format(          microwaveTime.getSecond() ) );      timeToDisplay = ""; // clear timeToDisplay for future input            clockTimer.start();                         // start timer      windowJPanel.setBackground( Color.YELLOW ); // turn "light" on   } // end method startJButtonActionPerformed      // clear the microwave oven   private void clearJButtonActionPerformed( ActionEvent event )   {      // stop Timer and reset variables to their initial settings      clockTimer.stop();      displayJTextField.setText( "Microwave Oven" );      timeToDisplay = "";      windowJPanel.setBackground( new Color( 204, 204, 204 ) );   } // end method clearJButtonActionPerformed   // display formatted time in displayJTextField   private void displayTime( String digit )   {      // append digit to timeToDisplay      timeToDisplay += digit;      // get the time as four digits      String fourDigitTime = formatTime();      // extract minutes and seconds      String minute = fourDigitTime.substring( 0, 2 );      String second = fourDigitTime.substring( 2 );      // display number of minutes, ":", then number of seconds      displayJTextField.setText( minute + ":" + second );   } // end method displayTime         // decrement displayJTextField by one second   private void clockTimerActionPerformed( ActionEvent event )   {      // decrement microwaveTime by one second      microwaveTime.tick();      // if microwaveTime has not reached zero      if ( !microwaveTime.isDone() )      {         // display remaining cooking time in displayJTextField         displayJTextField.setText( timeFormat.format(             microwaveTime.getMinute() ) + ":" + timeFormat.format(             microwaveTime.getSecond() ) );      } // end if      else // microwaveTime has reached zero      {         clockTimer.stop(); // stop timer                  // inform user timer is finished         displayJTextField.setText( "Done!" );         windowJPanel.setBackground( new Color( 204, 204, 204 ) );      } // end else         } // end method clockTimerActionPerformed      // main method   public static void main( String args[] )   {      MicrowaveOven application = new MicrowaveOven();      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );   } // end method main} // end class MicrowaveOven/************************************************************************** * (C) Copyright 1992-2004 by Deitel & Associates, Inc. and               * * Pearson Education, Inc. All Rights Reserved.                           * *                                                                        * * DISCLAIMER: The authors and publisher of this book have used their     * * best efforts in preparing the book. These efforts include the          * * development, research, and testing of the theories and programs        * * to determine their effectiveness. The authors and publisher make       * * no warranty of any kind, expressed or implied, with regard to these    * * programs or to the documentation contained in these books. The authors * * and publisher shall not be liable in any event for incidental or       * * consequential damages in connection with, or arising out of, the       * * furnishing, performance, or use of these programs.                     * **************************************************************************/